Publication
No difference between critical and sprint swimming speeds for two galaxiid species
Publisher:
Wiley
Date:
15-03-2023
DOI:
10.1111/JFB.15355
Abstract: Researchers have used laboratory experiments to examine how fish might be affected by anthropogenic alterations and conclude how best to adjust fish passage and culvert remediation designs in response. A common way to document swimming performance for this purpose is measuring fish critical swimming speed ( U crit ). Nonetheless, the U crit protocol as defined by Brett [(1964) Journal of the Fisheries Research Board of Canada , 21, 1183–1226] may be inappropriate for studying swimming performance and determining how it relates to upstream migration in benthic fish, as they may not actively swim throughout the entire U crit test. An alternative method to estimate swimming performance is sprint swimming speed ( U sprint ), which is suggested to be a measure of the burst speed of fish rather than maximum sustained swimming speed. The authors conducted comparative swimming performance experiments to evaluate whether U sprint can be used to compare swimming performance of benthic species to that of pelagic, actively swimming species. They measured in idual swimming speeds of īnanga ( Galaxias maculatus) , an actively swimming pelagic species, and banded kōkopu ( Galaxias fasciatus) , a fish that exhibits benthic station‐holding behaviour, using both the U sprint and U crit test. Experiments revealed that no significant statistical difference between swimming speeds was estimated using the U crit and U sprint test protocols for both G. maculatus and G. fasciatus . The result of this study suggests that fish swimming speeds obtained using these two methods are comparable for the species used in this study. By using U sprint for benthic‐associated fish and U crit for pelagic fish, we may be able to compare a broader range of species' swimming abilities for use in a fish passage context.